The proverb "Grass is always greener on the other side of the fence" means that people often believe that others have it better than they do, even if that isn't true. It suggests that we tend to focus on the things we lack and envy what others possess.
This can apply to many areas of life, like jobs, relationships, or living situations. For example, someone might think that their friend's job is more exciting, but they might not see the stress and long hours that come with it. Similarly, one might imagine city life is thrilling while overlooking the noise, pollution, and high costs. Везде хорошо, где нас нет translates to "It's always good where we are not."
It's important to remember that appearances can be deceiving, and that everyone faces their own challenges. Instead of always looking at what we don't have, we should appreciate what we do have and focus on making the most of our own situation. True happiness comes from contentment and gratitude, not from constantly comparing ourselves to others.